1 /* gzwrite.c -- zlib functions for writing gzip files
2 * Copyright (C) 2004-2017 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 #include "gzguts.h"
7
8 /* Local functions */
9 local int gz_init OF((gz_statep));
10 local int gz_comp OF((gz_statep, int));
11 local int gz_zero OF((gz_statep, z_off64_t));
12 local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));
13
14 /* Initialize state for writing a gzip file. Mark initialization by setting
15 state->size to non-zero. Return -1 on a memory allocation failure, or 0 on
16 success. */
gz_init(state)17 local int gz_init(state)
18 gz_statep state;
19 {
20 int ret;
21 z_streamp strm = &(state->strm);
22
23 /* allocate input buffer (double size for gzprintf) */
24 state->in = (unsigned char *)malloc(state->want << 1);
25 if (state->in == NULL) {
26 gz_error(state, Z_MEM_ERROR, "out of memory");
27 return -1;
28 }
29
30 /* only need output buffer and deflate state if compressing */
31 if (!state->direct) {
32 /* allocate output buffer */
33 state->out = (unsigned char *)malloc(state->want);
34 if (state->out == NULL) {
35 free(state->in);
36 gz_error(state, Z_MEM_ERROR, "out of memory");
37 return -1;
38 }
39
40 /* allocate deflate memory, set up for gzip compression */
41 strm->zalloc = Z_NULL;
42 strm->zfree = Z_NULL;
43 strm->opaque = Z_NULL;
44 ret = deflateInit2(strm, state->level, Z_DEFLATED,
45 MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
46 if (ret != Z_OK) {
47 free(state->out);
48 free(state->in);
49 gz_error(state, Z_MEM_ERROR, "out of memory");
50 return -1;
51 }
52 strm->next_in = NULL;
53 }
54
55 /* mark state as initialized */
56 state->size = state->want;
57
58 /* initialize write buffer if compressing */
59 if (!state->direct) {
60 strm->avail_out = state->size;
61 strm->next_out = state->out;
62 state->x.next = strm->next_out;
63 }
64 return 0;
65 }
66
67 /* Compress whatever is at avail_in and next_in and write to the output file.
68 Return -1 if there is an error writing to the output file or if gz_init()
69 fails to allocate memory, otherwise 0. flush is assumed to be a valid
70 deflate() flush value. If flush is Z_FINISH, then the deflate() state is
71 reset to start a new gzip stream. If gz->direct is true, then simply write
72 to the output file without compressing, and ignore flush. */
gz_comp(state,flush)73 local int gz_comp(state, flush)
74 gz_statep state;
75 int flush;
76 {
77 int ret, writ;
78 unsigned have, put, max = ((unsigned)-1 >> 2) + 1;
79 z_streamp strm = &(state->strm);
80
81 /* allocate memory if this is the first time through */
82 if (state->size == 0 && gz_init(state) == -1)
83 return -1;
84
85 /* write directly if requested */
86 if (state->direct) {
87 while (strm->avail_in) {
88 put = strm->avail_in > max ? max : strm->avail_in;
89 writ = write(state->fd, strm->next_in, put);
90 if (writ < 0) {
91 gz_error(state, Z_ERRNO, zstrerror());
92 return -1;
93 }
94 strm->avail_in -= (unsigned)writ;
95 strm->next_in += writ;
96 }
97 return 0;
98 }
99
100 /* run deflate() on provided input until it produces no more output */
101 ret = Z_OK;
102 do {
103 /* write out current buffer contents if full, or if flushing, but if
104 doing Z_FINISH then don't write until we get to Z_STREAM_END */
105 if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
106 (flush != Z_FINISH || ret == Z_STREAM_END))) {
107 while (strm->next_out > state->x.next) {
108 put = strm->next_out - state->x.next > (int)max ? max :
109 (unsigned)(strm->next_out - state->x.next);
110 writ = write(state->fd, state->x.next, put);
111 if (writ < 0) {
112 gz_error(state, Z_ERRNO, zstrerror());
113 return -1;
114 }
115 state->x.next += writ;
116 }
117 if (strm->avail_out == 0) {
118 strm->avail_out = state->size;
119 strm->next_out = state->out;
120 state->x.next = state->out;
121 }
122 }
123
124 /* compress */
125 have = strm->avail_out;
126 ret = deflate(strm, flush);
127 if (ret == Z_STREAM_ERROR) {
128 gz_error(state, Z_STREAM_ERROR,
129 "internal error: deflate stream corrupt");
130 return -1;
131 }
132 have -= strm->avail_out;
133 } while (have);
134
135 /* if that completed a deflate stream, allow another to start */
136 if (flush == Z_FINISH)
137 deflateReset(strm);
138
139 /* all done, no errors */
140 return 0;
141 }
142
143 /* Compress len zeros to output. Return -1 on a write error or memory
144 allocation failure by gz_comp(), or 0 on success. */
gz_zero(state,len)145 local int gz_zero(state, len)
146 gz_statep state;
147 z_off64_t len;
148 {
149 int first;
150 unsigned n;
151 z_streamp strm = &(state->strm);
152
153 /* consume whatever's left in the input buffer */
154 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
155 return -1;
156
157 /* compress len zeros (len guaranteed > 0) */
158 first = 1;
159 while (len) {
160 n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
161 (unsigned)len : state->size;
162 if (first) {
163 memset(state->in, 0, n);
164 first = 0;
165 }
166 strm->avail_in = n;
167 strm->next_in = state->in;
168 state->x.pos += n;
169 if (gz_comp(state, Z_NO_FLUSH) == -1)
170 return -1;
171 len -= n;
172 }
173 return 0;
174 }
175
176 /* Write len bytes from buf to file. Return the number of bytes written. If
177 the returned value is less than len, then there was an error. */
gz_write(state,buf,len)178 local z_size_t gz_write(state, buf, len)
179 gz_statep state;
180 voidpc buf;
181 z_size_t len;
182 {
183 z_size_t put = len;
184
185 /* if len is zero, avoid unnecessary operations */
186 if (len == 0)
187 return 0;
188
189 /* allocate memory if this is the first time through */
190 if (state->size == 0 && gz_init(state) == -1)
191 return 0;
192
193 /* check for seek request */
194 if (state->seek) {
195 state->seek = 0;
196 if (gz_zero(state, state->skip) == -1)
197 return 0;
198 }
199
200 /* for small len, copy to input buffer, otherwise compress directly */
201 if (len < state->size) {
202 /* copy to input buffer, compress when full */
203 do {
204 unsigned have, copy;
205
206 if (state->strm.avail_in == 0)
207 state->strm.next_in = state->in;
208 have = (unsigned)((state->strm.next_in + state->strm.avail_in) -
209 state->in);
210 copy = state->size - have;
211 if (copy > len)
212 copy = len;
213 memcpy(state->in + have, buf, copy);
214 state->strm.avail_in += copy;
215 state->x.pos += copy;
216 buf = (const char *)buf + copy;
217 len -= copy;
218 if (len && gz_comp(state, Z_NO_FLUSH) == -1)
219 return 0;
220 } while (len);
221 }
222 else {
223 /* consume whatever's left in the input buffer */
224 if (state->strm.avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
225 return 0;
226
227 /* directly compress user buffer to file */
228 state->strm.next_in = (z_const Bytef *)buf;
229 do {
230 unsigned n = (unsigned)-1;
231 if (n > len)
232 n = len;
233 state->strm.avail_in = n;
234 state->x.pos += n;
235 if (gz_comp(state, Z_NO_FLUSH) == -1)
236 return 0;
237 len -= n;
238 } while (len);
239 }
240
241 /* input was all buffered or compressed */
242 return put;
243 }
244
245 /* -- see zlib.h -- */
gzwrite(file,buf,len)246 int ZEXPORT gzwrite(file, buf, len)
247 gzFile file;
248 voidpc buf;
249 unsigned len;
250 {
251 gz_statep state;
252
253 /* get internal structure */
254 if (file == NULL)
255 return 0;
256 state = (gz_statep)file;
257
258 /* check that we're writing and that there's no error */
259 if (state->mode != GZ_WRITE || state->err != Z_OK)
260 return 0;
261
262 /* since an int is returned, make sure len fits in one, otherwise return
263 with an error (this avoids a flaw in the interface) */
264 if ((int)len < 0) {
265 gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
266 return 0;
267 }
268
269 /* write len bytes from buf (the return value will fit in an int) */
270 return (int)gz_write(state, buf, len);
271 }
272
273 /* -- see zlib.h -- */
gzfwrite(buf,size,nitems,file)274 z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
275 voidpc buf;
276 z_size_t size;
277 z_size_t nitems;
278 gzFile file;
279 {
280 z_size_t len;
281 gz_statep state;
282
283 /* get internal structure */
284 if (file == NULL)
285 return 0;
286 state = (gz_statep)file;
287
288 /* check that we're writing and that there's no error */
289 if (state->mode != GZ_WRITE || state->err != Z_OK)
290 return 0;
291
292 /* compute bytes to read -- error on overflow */
293 len = nitems * size;
294 if (size && len / size != nitems) {
295 gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
296 return 0;
297 }
298
299 /* write len bytes to buf, return the number of full items written */
300 return len ? gz_write(state, buf, len) / size : 0;
301 }
302
303 /* -- see zlib.h -- */
gzputc(file,c)304 int ZEXPORT gzputc(file, c)
305 gzFile file;
306 int c;
307 {
308 unsigned have;
309 unsigned char buf[1];
310 gz_statep state;
311 z_streamp strm;
312
313 /* get internal structure */
314 if (file == NULL)
315 return -1;
316 state = (gz_statep)file;
317 strm = &(state->strm);
318
319 /* check that we're writing and that there's no error */
320 if (state->mode != GZ_WRITE || state->err != Z_OK)
321 return -1;
322
323 /* check for seek request */
324 if (state->seek) {
325 state->seek = 0;
326 if (gz_zero(state, state->skip) == -1)
327 return -1;
328 }
329
330 /* try writing to input buffer for speed (state->size == 0 if buffer not
331 initialized) */
332 if (state->size) {
333 if (strm->avail_in == 0)
334 strm->next_in = state->in;
335 have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
336 if (have < state->size) {
337 state->in[have] = (unsigned char)c;
338 strm->avail_in++;
339 state->x.pos++;
340 return c & 0xff;
341 }
342 }
343
344 /* no room in buffer or not initialized, use gz_write() */
345 buf[0] = (unsigned char)c;
346 if (gz_write(state, buf, 1) != 1)
347 return -1;
348 return c & 0xff;
349 }
350
351 /* -- see zlib.h -- */
gzputs(file,str)352 int ZEXPORT gzputs(file, str)
353 gzFile file;
354 const char *str;
355 {
356 int ret;
357 z_size_t len;
358 gz_statep state;
359
360 /* get internal structure */
361 if (file == NULL)
362 return -1;
363 state = (gz_statep)file;
364
365 /* check that we're writing and that there's no error */
366 if (state->mode != GZ_WRITE || state->err != Z_OK)
367 return -1;
368
369 /* write string */
370 len = strlen(str);
371 ret = gz_write(state, str, len);
372 return ret == 0 && len != 0 ? -1 : ret;
373 }
374
375 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
376 #include <stdarg.h>
377
378 /* -- see zlib.h -- */
gzvprintf(gzFile file,const char * format,va_list va)379 int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
380 {
381 int len;
382 unsigned left;
383 char *next;
384 gz_statep state;
385 z_streamp strm;
386
387 /* get internal structure */
388 if (file == NULL)
389 return Z_STREAM_ERROR;
390 state = (gz_statep)file;
391 strm = &(state->strm);
392
393 /* check that we're writing and that there's no error */
394 if (state->mode != GZ_WRITE || state->err != Z_OK)
395 return Z_STREAM_ERROR;
396
397 /* make sure we have some buffer space */
398 if (state->size == 0 && gz_init(state) == -1)
399 return state->err;
400
401 /* check for seek request */
402 if (state->seek) {
403 state->seek = 0;
404 if (gz_zero(state, state->skip) == -1)
405 return state->err;
406 }
407
408 /* do the printf() into the input buffer, put length in len -- the input
409 buffer is double-sized just for this function, so there is guaranteed to
410 be state->size bytes available after the current contents */
411 if (strm->avail_in == 0)
412 strm->next_in = state->in;
413 next = (char *)(state->in + (strm->next_in - state->in) + strm->avail_in);
414 next[state->size - 1] = 0;
415 #ifdef NO_vsnprintf
416 # ifdef HAS_vsprintf_void
417 (void)vsprintf(next, format, va);
418 for (len = 0; len < state->size; len++)
419 if (next[len] == 0) break;
420 # else
421 len = vsprintf(next, format, va);
422 # endif
423 #else
424 # ifdef HAS_vsnprintf_void
425 (void)vsnprintf(next, state->size, format, va);
426 len = strlen(next);
427 # else
428 len = vsnprintf(next, state->size, format, va);
429 # endif
430 #endif
431
432 /* check that printf() results fit in buffer */
433 if (len == 0 || (unsigned)len >= state->size || next[state->size - 1] != 0)
434 return 0;
435
436 /* update buffer and position, compress first half if past that */
437 strm->avail_in += (unsigned)len;
438 state->x.pos += len;
439 if (strm->avail_in >= state->size) {
440 left = strm->avail_in - state->size;
441 strm->avail_in = state->size;
442 if (gz_comp(state, Z_NO_FLUSH) == -1)
443 return state->err;
444 memcpy(state->in, state->in + state->size, left);
445 strm->next_in = state->in;
446 strm->avail_in = left;
447 }
448 return len;
449 }
450
gzprintf(gzFile file,const char * format,...)451 int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
452 {
453 va_list va;
454 int ret;
455
456 va_start(va, format);
457 ret = gzvprintf(file, format, va);
458 va_end(va);
459 return ret;
460 }
461
462 #else /* !STDC && !Z_HAVE_STDARG_H */
463
464 /* -- see zlib.h -- */
gzprintf(file,format,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)465 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
466 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
467 gzFile file;
468 const char *format;
469 int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
470 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
471 {
472 unsigned len, left;
473 char *next;
474 gz_statep state;
475 z_streamp strm;
476
477 /* get internal structure */
478 if (file == NULL)
479 return Z_STREAM_ERROR;
480 state = (gz_statep)file;
481 strm = &(state->strm);
482
483 /* check that can really pass pointer in ints */
484 if (sizeof(int) != sizeof(void *))
485 return Z_STREAM_ERROR;
486
487 /* check that we're writing and that there's no error */
488 if (state->mode != GZ_WRITE || state->err != Z_OK)
489 return Z_STREAM_ERROR;
490
491 /* make sure we have some buffer space */
492 if (state->size == 0 && gz_init(state) == -1)
493 return state->error;
494
495 /* check for seek request */
496 if (state->seek) {
497 state->seek = 0;
498 if (gz_zero(state, state->skip) == -1)
499 return state->error;
500 }
501
502 /* do the printf() into the input buffer, put length in len -- the input
503 buffer is double-sized just for this function, so there is guaranteed to
504 be state->size bytes available after the current contents */
505 if (strm->avail_in == 0)
506 strm->next_in = state->in;
507 next = (char *)(strm->next_in + strm->avail_in);
508 next[state->size - 1] = 0;
509 #ifdef NO_snprintf
510 # ifdef HAS_sprintf_void
511 sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
512 a13, a14, a15, a16, a17, a18, a19, a20);
513 for (len = 0; len < size; len++)
514 if (next[len] == 0)
515 break;
516 # else
517 len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
518 a12, a13, a14, a15, a16, a17, a18, a19, a20);
519 # endif
520 #else
521 # ifdef HAS_snprintf_void
522 snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
523 a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
524 len = strlen(next);
525 # else
526 len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8,
527 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
528 # endif
529 #endif
530
531 /* check that printf() results fit in buffer */
532 if (len == 0 || len >= state->size || next[state->size - 1] != 0)
533 return 0;
534
535 /* update buffer and position, compress first half if past that */
536 strm->avail_in += len;
537 state->x.pos += len;
538 if (strm->avail_in >= state->size) {
539 left = strm->avail_in - state->size;
540 strm->avail_in = state->size;
541 if (gz_comp(state, Z_NO_FLUSH) == -1)
542 return state->err;
543 memcpy(state->in, state->in + state->size, left);
544 strm->next_in = state->in;
545 strm->avail_in = left;
546 }
547 return (int)len;
548 }
549
550 #endif
551
552 /* -- see zlib.h -- */
gzflush(file,flush)553 int ZEXPORT gzflush(file, flush)
554 gzFile file;
555 int flush;
556 {
557 gz_statep state;
558
559 /* get internal structure */
560 if (file == NULL)
561 return Z_STREAM_ERROR;
562 state = (gz_statep)file;
563
564 /* check that we're writing and that there's no error */
565 if (state->mode != GZ_WRITE || state->err != Z_OK)
566 return Z_STREAM_ERROR;
567
568 /* check flush parameter */
569 if (flush < 0 || flush > Z_FINISH)
570 return Z_STREAM_ERROR;
571
572 /* check for seek request */
573 if (state->seek) {
574 state->seek = 0;
575 if (gz_zero(state, state->skip) == -1)
576 return state->err;
577 }
578
579 /* compress remaining data with requested flush */
580 (void)gz_comp(state, flush);
581 return state->err;
582 }
583
584 /* -- see zlib.h -- */
gzsetparams(file,level,strategy)585 int ZEXPORT gzsetparams(file, level, strategy)
586 gzFile file;
587 int level;
588 int strategy;
589 {
590 gz_statep state;
591 z_streamp strm;
592
593 /* get internal structure */
594 if (file == NULL)
595 return Z_STREAM_ERROR;
596 state = (gz_statep)file;
597 strm = &(state->strm);
598
599 /* check that we're writing and that there's no error */
600 if (state->mode != GZ_WRITE || state->err != Z_OK)
601 return Z_STREAM_ERROR;
602
603 /* if no change is requested, then do nothing */
604 if (level == state->level && strategy == state->strategy)
605 return Z_OK;
606
607 /* check for seek request */
608 if (state->seek) {
609 state->seek = 0;
610 if (gz_zero(state, state->skip) == -1)
611 return state->err;
612 }
613
614 /* change compression parameters for subsequent input */
615 if (state->size) {
616 /* flush previous input with previous parameters before changing */
617 if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
618 return state->err;
619 deflateParams(strm, level, strategy);
620 }
621 state->level = level;
622 state->strategy = strategy;
623 return Z_OK;
624 }
625
626 /* -- see zlib.h -- */
gzclose_w(file)627 int ZEXPORT gzclose_w(file)
628 gzFile file;
629 {
630 int ret = Z_OK;
631 gz_statep state;
632
633 /* get internal structure */
634 if (file == NULL)
635 return Z_STREAM_ERROR;
636 state = (gz_statep)file;
637
638 /* check that we're writing */
639 if (state->mode != GZ_WRITE)
640 return Z_STREAM_ERROR;
641
642 /* check for seek request */
643 if (state->seek) {
644 state->seek = 0;
645 if (gz_zero(state, state->skip) == -1)
646 ret = state->err;
647 }
648
649 /* flush, free memory, and close file */
650 if (gz_comp(state, Z_FINISH) == -1)
651 ret = state->err;
652 if (state->size) {
653 if (!state->direct) {
654 (void)deflateEnd(&(state->strm));
655 free(state->out);
656 }
657 free(state->in);
658 }
659 gz_error(state, Z_OK, NULL);
660 free(state->path);
661 if (close(state->fd) == -1)
662 ret = Z_ERRNO;
663 free(state);
664 return ret;
665 }
666